Say Jax v Irelia top. Heimer v Ziggs mid. Heimer died to Ziggs once and wanted to lane swap.
-> Irelia went mid v Ziggs. Heimer went top v Jax.
-> Ziggs can't deal with Irelia, wanted to lane swap.
-> Jax went mid v Irelia. Ziggs went top v Heimer.
-> The game went on.
In the end, Jax earned LP for going mid.